The B-66 Helped Define What It Meant to Be a Multi-Role Jet
The Douglas B-66 Destroyer was developed during the early 1950s for the US Air Force as a jet-powered replacement for the World War II-vintage Douglas A-26 Invader, the North American B-45 Tornado, and the Martin B-57 Canberra. Air Force specifications called for the new jet bomber to deliver a 10,000 pound payload (including “special” weapons) with 1,000 nautical mile range.
Not an Air Force Whale
Developed from the Douglas A-3 Skywarrior built for the US Navy, the B-66 was originally intended to be essentially an A-3 with only the Navy-specific equipment required for carrier operations, such as folding wings and vertical stabilizer, arresting gear, and catapult bridle hooks, removed from the Air Force B-66. But the Destroyer was eventually modified so many times that by the time the aircraft reached operational status with the Air Force the two jets shared very few common parts and the B-66 outweighed the A-3 by a little bit more than 10,000 pounds.
The Destroyer Difference
The Air Force requirement for low altitude operations required additional strength in the fuselage and wings. The B-66 wing had a revised layout with increased area yielding greater lift, a thinner cross-section, revised incidence angle, and revised ailerons, spoilers, and flaps. B-66 hydraulic and fuel systems were revised along with the landing gear, which were equipped with bigger tires for rough field operations. The B-66 nose and canopy were distinctive due to the presence of the ejection seats, a different radar system, and the required larger radar antenna.
Could Have Had More Power
The use of Allison J71 turbojet engines and the presence of ejection seats for the crew of three in the B-66 were the two primary operational differences between the two aircraft. The A-3 was powered by Pratt & Whitney J57 turbojets and lacked ejection seats for the crew. Those J71 engines would prove to be the major limiting factor in the operational success of the B-66.
Could Have Had More Power, But…
The Air Force opted for the under-powered J71 engines instead of Pratt & Whitney J57s because other aircraft in production and in planning at the time, such as the Boeing B-52 Stratofortress strategic bomber, the Boeing KC-135 Stratotanker for Strategic Air Command (SAC) as well as the North American F-100 Super Sabre, the McDonnell F-101 Voodoo, and the Convair F-102 Delta Dagger for Tactical Air Command (TAC) and Air Defense Command (ADC), all had priority over for engine procurement over the B-66. The Navy needed J57 engines for the Vought F-8 Crusader.
Engineering to the Rescue
The reconnaissance version of the B-66, designated RB-66A, was actually the first version of the aircraft to go into production and was later produced concurrently with the bomber version of the airframe. The initial five RB-66A aircraft produced by Douglas had so many problems that the Air Force considered cancellation of the program and began a search for a replacement. Because fixes for most of the issues, such as poor handling, restricted outward vision, malfunctioning landing gear doors, wing vibrations and buffeting, and a propensity for pitching up had been identified, the program was allowed to continue.
Multi-Role Before It Was Cool
Like the A-3, the B-66 was adapted for use in multiple roles. The RB-66A and RB-66B were all-weather reconnaissance versions. The B-66B was the straight bomber version, actually developed from the RB-66B. The RB-66C, EB-66C, and EB-66E were all electronic reconnaissance and countermeasures versions with four electronic warfare officers housed in the bomb bay sitting on downward-firing ejection seats added to the crew. The WB-66D was a weather reconnaissance version.